Archived Kit Documentation

Raspberry Pi QRP TX Shield for WSPR on 30 Meters

Nowadays, one of the most impressive QRP modes is Joe Taylor, K1JT's WSPR
(pronounced "whisper") mode. WSPR stands for "Weak Signal Propagation
Reporter." Programs written for WSPR mode are designed for sending and
receiving low-power transmissions to test propagation paths on the MF,
HF and recently, UHF bands. The process is similar to a beacon. Users with Internet access can watch results
in real time at wsprnet.org.

WSPR Without
Tears is Bruce Raymond, ND8I's project to simplify the process of getting an actual transmitter up and running so you can enjoy
working with WSPR and avoid dealing with the headaches associated with building a working system. What
makes it really interesting is that WSPR is optimized for operating at very low power. Our kit puts out a
whopping 200 mW which is capable of reaching impressive distances even with a bad antenna (see the map above for typical response using an-end fed dipole in an attic).
The QRPi board (or shield as referred by the community today) is an
inexpensive way of turning a Raspberry Pi single-board computer into a
QRP transmitter.

Our approach uses a Raspberry Pi computer ($35) to generate WSPR transmissions. Our board plugs into a
Raspberry Pi and amplifies and filters the output (the Raspberry Pi output is a very low power square wave
that would be illegal to transmit due to its harmonic content). The Raspberry Pi generates the WSPR
signal in software and utilizes timing data from the Internet to calibrate its internal clock and transmit
frequency, so you don't have to do it.

So join the group of Whispering Raspberries on 30 meters by ordering a
TAPR 30M-WSPR-Pi today.

Pablo, WA6RSV, alerted us to the fact that not everyone realizes what a
Raspberry Pi is. He said, "One week ago I thought a Raspberry Pi was a
dessert! (I like apple pie!). Nobody explained to me that it is a normal
computer just like your Mac or PC. You can use it just like a Windows
PC to browse the Internet, write an email, etc. The concept is as
follows 1) you buy it and you plug in a monitor, USB mouse and USB
keyboard. 2) If the MicroSD does not have the operating system (Like
Windows or OSX, but for this contraption it's called
NOOBS/Raspbian) you go get it at www.raspberrypi.org and copy
it into the MicroSD which is also the hard drive/RAM ) After installing
the operating system it will work like a NORMAL computer with
everything including the built in WIFI (if a Pi 3)."

Note: The "WSPR Without Tears" kit comes with a programmed MicroSD card.
Note: The "WSPR Without Tears" kit also includes an end-fed 30M antenna kit too. See the Antenna Quickstart Guide below.Note: The "WSPR Without Tesrs" kit does not include the Raspberry Pi.